<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <script src="vue.js"></script>
    <title>Document</title>
    <style>
        .ball{
            width:15px;
            height: 15px;
            background-color: hotpink;
            border-radius: 50%;
        }
    </style>
</head>

<body>
    <div id="app">
        <input type="button" value="加入购物车" @click="flag=!flag">
        <transition @before-enter="beforeEnter" @enter="enter" @after-enter="afterEnter">
            <div class="ball" v-show="flag"></div>
        </transition>
    </div>
</body>

<script>
    var vm = new Vue({
        el: '#app',
        data: {
            flag: false
        },
        methods: {
            beforeEnter(el) {
                el.style.transform = 'translate(0,0)'
            },
            enter(el, done) {
                el.offsetWidth
                el.style.transform = 'translate(150px,450px)'
                el.style.transition = 'all 1s ease'
                done()
            },
            afterEnter(el) {
                this.flag = !this.flag
            }

        }

    })
</script>

</html>